diff --git a/.gitconfig b/.gitconfig
index 1d62cb0..1ed4f9f 100644
--- a/.gitconfig
+++ b/.gitconfig
@@ -10,4 +10,8 @@
 	type = cat-file -t
 	dump = cat-file -p
 [push]
+        # 1.7.1:  nothing, matching, tracking, current
+        # 2.11.0: nothing, matching, upstream, current, simple
+        # nothing is inconvenient, matching is dangerous. 
+        # current is only compatible remaining option.
 	default = current